Lead electric vehicle batteries

The battery capacity represents the electric charge that a battery can supply. Instead of using the Coulomb, which is the SI unit for the electric capacity but is an inconveniently small unit, the Amphour (Ah) is commonly used to refer to the capacity of electric vehicle batteries. Batteries are characterized by a nominal value of capacity, determined with predefined procedures. However, the real capacity of a battery depends on the current values drawn out from it. This changing in the expected capacity is caused by uncompleted or unwanted reactions inside the cell. This effect occurs in all the types of batteries, but it is particularly accentuated for lead-acid batteries. Figure 5.13 shows typical discharge curves for different discharge rates (/j, where the black line shows the available... 

USABC has set the goal so high that lead-acid batteries have been put out of the question for this application [29]. This led to an initiative by the lead-acid battery industry and their suppliers to set up the Advanced Lead-Acid Battery Consortium (ALABC) with the goal of fostering development of the lead-acid battery for use in electric vehicles, at least for an interim period until more powerful batteries with higher energy density will become available. Here a series of complex technical problems have to be solved [30]. Of course, such electric vehicle batteries have to be maintenance-free, that is, of sealed construction the resulting use of lead-calcium alloys and thus the premature capacity loss have already been touched on. 

THE INTERNATIONAL LEAD TRADE Table 18.1 Alternative electric vehicle battery systems... 

This 2.6 V battery is at pilot plant production stage as a possible electric vehicle battery. Eagle Picher (US) are leading workers in this field. 

The future use of lead may be decided by the resolution of an environmental paradox. Some markets for lead are being phased out because of environmental concerns, eg, the use of tetraethyllead as a gasoline additive. However, a 1990 State of California law and similar laws in nine eastern U.S. states require that 2% of new cars meet 2ero-emission standards in 1998. By 2003 this requirement rises to 10% of new vehicles. Zero emission vehicles are generally accepted to mean electric, ie, battery powered cars, and there is considerable research effort to bring suitable electric vehicles to market by 1998. 

Because the nickel—iron cell system has a low cell voltage and high cost compared to those of the lead—acid battery, lead—acid became the dorninant automotive and industrial battery system except for heavy-duty appHcations. Renewed interest in the nickel—iron and nickel—cadmium systems, for electric vehicles started in the mid-1980s using other cell geometries. 

In the 1990s, the use of batteries in electric vehicles and for load leveling is being revived partly for environmental reasons and partly because of scarce energy resources. Improvements in battery performance and life, fewer maintenance requirements, and automatic control systems are making these appHcations feasible. Research and development is ongoing all over the world to develop improved lead—acid batteries as weU as other systems to meet these needs. 

Alternatives to coal and hydrocarbon fuels as a source of power have been sought with increasing determination over the past three decades. One possibility is the Hydrogen Economy (p, 40), Another possibility, particularly for secondary, mobile sources of power, is the use of storage batteries. Indeed, electric vehicles were developed simultaneously with the first intemal-combustion-cngined vehicles, the first being made in 1888. In those days, over a century ago, electric vehicles were popular and sold well compared with the then noisy, inconvenient and rather unreliable peU ol-engined vehicles. In 1899 an electric car held the world land-speed record at 105 km per hour. In the early years of this century, taxis in New York, Boston and Berlin were mainly electric there were over 20000 electi ic vehicles in the USA and some 10000 cars and commercial vehicles in London. Even today (silent) battery-powered milk delivery vehicles are still operated in the UK. These use the traditional lead-sulfuric acid battery (p. 371), but this is extremely heavy and rather expensive. 

To further reduce weight and improve energy density, several companies are developing thin lead film electrodes in a spiral-wound construction with glass fiber separators. Already on the market for cordless electric tools, this battery technology may eventually be used in electric vehicles. 

Electric road vehicles have been reduced to insignificance, as mentioned already by, vehicles with combustion engines. Another electric vehicle — the electrically driven submarine — presented a continuous challenge to lead-acid battery separator development since the 1930s and 1940s. The wood veneers originally used in electric vehicles proved too difficult to handle, especially if tall cells had to be manufactured. Therefore much intense effort took place to develop the first plastic separators. In this respect the microporous hard rubber separator, still available today in a more advanced version, and a micro-porous PVC separator (Porvic I) merit special mention 28]. For the latter a molten blend of PVC, plasticizer and starch was rolled into a flat product. In a lengthy pro-... 

As stated previously, a battery is an electrochemical device with the ability to convert chemical energy to electrical energy to provide power to electronic devices. Household batteries may also contain cadmium, mercury, copper, zinc, lead, manganese, nickel, and lithium, which may create a hazard when disposed incorrectly. The potential problems or hazards of household batteries are similar to that of vehicle batteries. 

NiMH batteries can power an electric vehicle for over 100 miles, but are still several times more expensive than lead-acid. NiMH batteries from Energy Conversion Devices were installed in GM s EVj and S-10 electric pickup truck, doubling the range of each. Chrysler has also used... 

U.S. Electricar built the lead-acid Electricar Prizm in Torrance, California, at Hughes Power Control Systems, a GM subsidiary that also designed the car s DC-to-AC inverter. Instead of a gas gauge there was a range meter. The batteries were in a covered tunnel underneath the car. Most electric vehicles have good low-end torque for excellent 0-60 acceleration, but the Prizm was a little sluggish initially but then picked up quickly. The car used a recharging paddle. 

GM built an electric vehicle (EV) called the Electrovette in 1980. It was a Chevette with a DC electric motor and zinc nickel oxide batteries. The Electrovette used a mechanical controller. The batteries were expensive and not much better than lead-acid power for extending the range of operation. The Electrovette had controller problems and GM let the project die. 

Battery-electric vehicles would lead to relatively low WTW GHG emissions, even if electricity from the EU electricity mix is used. 

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